Sintered powder containing a near-infrared reflector for producing moulded bodies

Abstract

The present invention relates to a process for producing a shaped body, wherein, in step i), a layer of a sinter powder (SP) comprising at least one near infrared reflector inter alia is provided and, in step ii), the layer provided in step i) is exposed. The present invention further relates to a process for producing a sinter powder (SP) and to the sinter powder (SP) obtainable by this process, and to the use of a near infrared reflector in a sinter powder (SP). The present invention also relates to a shaped body obtainable by the process of the invention.

1 .- 14 . (canceled) 
     
     
         15 . A process for producing a shaped body, comprising the steps of:
 i) providing a layer of a sinter powder (SP) comprising the following components:
 (A) at least one semicrystalline polyamide, 
 (B) at least one amorphous polyamide, 
 (C) at least one near infrared reflector, 
   ii) exposing the layer of the sinter powder (SP) provided in step i), wherein the sinter powder (SP) comprises in the range from 50% to 94.95% by weight of component (A), in the range from 5% to 40% by weight of component (B) and in the range from 0.05% to 10% by weight of component (C), based in each case on the total weight of the sinter powder (SP).   
     
     
         16 . The process according to  claim 15 , wherein component (C) reflects radiation with a wavelength in the range from 780 nm to 2.5 μm to an extent of at least 60%. 
     
     
         17 . The process according to  claim 15 , wherein component (C) is selected from the group consisting of near infrared-reflecting pigments. 
     
     
         18 . The process according to  claim 15 , wherein the exposing in step ii) is effected with a radiation source selected from the group consisting of lasers and infrared sources. 
     
     
         19 . The process according to  claim 15 , wherein component (A) is selected from the group consisting of PA 4, PA 6, PA 7, PA 8, PA 9, PA 11, PA 12, PA 46, PA 66, PA 69, PA 6.10, PA 6.12, PA 6.13, PA 6/6.36, PA 12.12, PA 13.13, PA 6T, PA6T/6, PA MXD6, PA 6/66, PA 6/12 and copolyamides of these. 
     
     
         20 . The process according to  claim 15 , wherein component (B) is selected from the group consisting of PA 6I/6T, PA 6I and PA 6/3T. 
     
     
         21 . The process according to  claim 15 , wherein the following step is conducted between step i) and step ii):
 i-1) applying at least one IR-absorbing ink to at least part of the layer of the sinter powder (SP) provided in step i).   
     
     
         22 . The process according to  claim 15 , wherein the sinter powder (SP) additionally comprises in the range from 0.1% to 10% by weight of at least one additive selected from the group consisting of antinucleating agents, stabilizers and end group functionalizers, based on the total weight of the sinter powder (SP). 
     
     
         23 . The process according to  claim 15 , wherein component (C) in the sinter powder (SP) has been coated with component (A) and/or with component (B). 
     
     
         24 . A process for producing a sinter powder (SP), comprising the steps of
 a) mixing the following components:
 (A) at least one semicrystalline polyamide, 
 (B) at least one amorphous polyamide, 
 (C) at least one near infrared reflector, 
   b) grinding the mixture obtained in step a) to obtain the sinter powder (SP), wherein the sinter powder (SP) comprises in the range from 50% to 94.95% by weight of component (A), in the range from 5% to 40% by weight of component (B) and in the range from 0.05% to 10% by weight of component (C), based in each case on the total weight of the sinter powder (SP).   
     
     
         25 . A sinter powder (SP) obtainable by the process according to  claim 24 , wherein the sinter powder (SP) comprises in the range from 50% to 94.95% by weight of component (A), in the range from 5% to 40% by weight of component (B) and in the range from 0.05% to 10% by weight of component (C), based in each case on the total weight of the sinter powder (SP). 
     
     
         26 . A process for reducing warpage in the production of shaped bodies from the sinter powder (SP) which comprises exposing the sinter powder (SP) wherein the sinter powder (SP) comprising the following components:
 (A) at least one semicrystalline polyamide,   (B) at least one amorphous polyamide and   (C) at least one near infrared reflector.   
     
     
         27 . A sintering process which comprises the step of utilizing the sinter powder (SP) as claimed in  claim 25 . 
     
     
         28 . A shaped body obtainable by the process according to  claim 15 , wherein the sinter powder (SP) comprises in the range from 50% to 94.95% by weight of component (A), in the range from 5% to 40% by weight of component (B) and in the range from 0.05% to 10% by weight of component (C), based in each case on the total weight of the sinter powder (SP).